The PC-39 is an aluminium case, of course; Lian Li don't make cases out of anything else. It's got Lian Li's trademark hard anodised brushed metal finish. Looks good, quite hard wearing, not too susceptible to finger-marks.
The fronts of the two racks match the aluminium front panel well, but they're not actually metal; they're plastic. The main part of each rack tray, where you install the drive, is aluminium, so the drive should get decent cooling. The racks are both lockable.
